2004 Envoy dies

While driving the engine does not shut off but loses all power. You turn the key off and restart the motor and your off to the races again for a short time. Power steering and braking are not affected. Closest thing I can relate it to is running into a rev limiter but the engine is just at idle. Any suggestions as what this might be? The shop pulled up 13 electrical type codes and arent sure whats going on.

P.S. I am posting this for someone else so i am not sure of all the exact details.

1) How old is the battery?
2) How old is the fuel filter?
3) Doe's weather like snow, rain, ice, or a car wash play a factor?
4) Have both the battery + alternator load tested.
5) Rolled the fuel pump relay to another pos.
6) Have the catalytic converters back pressure tested at a local muffler shop.

As you say, without the details where would that leave us in respect to helping you, the codes would be a starting point.